Methods and systems for generating carbon disulfide

Abstract

The present application pertains to a method of making carbon disulfide. The method comprises reacting methane and sulfur under conditions sufficient to produce carbon disulfide, hydrogen disulfide, and heat. At least a portion of the produced hydrogen disulfide is reacted with methane under conditions sufficient to produce a mixture comprising carbon disulfide and hydrogen. Advantageously, at least a portion of the heat from reacting methane and sulfur is employed in the reacting of at least a portion of the produced hydrogen disulfide with methane.

We claim: 
     
         1 . A method for making carbon disulfide comprising:
 reacting methane and sulfur under conditions sufficient to produce carbon disulfide, hydrogen disulfide, and heat; and   reacting at least a portion of the produced hydrogen disulfide with methane under conditions sufficient to produce a mixture comprising carbon disulfide and hydrogen;   
       wherein at least a portion of the heat from reacting methane and sulfur is employed in the reacting of the at least the portion of the produced hydrogen disulfide with methane. 
     
     
         2 . The method of  claim 1  which further comprises separating carbon disulfide and hydrogen disulfide. 
     
     
         3 . The method of  claim 1  which further comprises separating carbon disulfide from hydrogen sulfide and hydrogen in the mixture. 
     
     
         4 . The method of  claim 3  which further comprises separating hydrogen from hydrogen sulfide. 
     
     
         5 . The method of  claim 4  which further comprises compressing the separated hydrogen. 
     
     
         6 . The method of  claim 4  which further comprises blending said separated hydrogen into fuel gas. 
     
     
         7 . The method of  claim 2  which further comprises employing at least a portion of said separated carbon disulfide in another process. 
     
     
         8 . The method of  claim 3  which further comprises employing at least a portion of said separated carbon disulfide in another process. 
     
     
         9 . The method of  claim 4  which further comprises employing at least a portion of said separated hydrogen as fuel in the reacting at least a portion of the produced hydrogen disulfide with methane. 
     
     
         10 . The method of  claim 1  further comprising recycling at least a portion of any unreacted sulfur in the reacting of methane and sulfur. 
     
     
         11 . The method of  claim 1  wherein the heat comprises steam. 
     
     
         12 . The method of  claim 11  which further comprises converting at least a portion of the steam to generate electricity. 
     
     
         13 . The method of  claim 12  wherein at least a portion of the generated electricity is employed in the reacting of the at least the portion of the produced hydrogen disulfide with methane. 
     
     
         14 . The method of  claim 1  which further comprises cooling the mixture comprising carbon disulfide and hydrogen. 
     
     
         15 . The method of  claim 1  wherein the reacting of methane and sulfur is conducted a reactor pressure of from about 0.5 barg to about 3.5 barg. 
     
     
         16 . The method of  claim 1  wherein the reacting of methane and sulfur is conducted a reactor pressure of from about 1.2 barg to about 2.4 barg. 
     
     
         17 . The method of  claim 1  wherein the reacting of methane and sulfur is conducted at a reactor temperature of from about 500° C. to about 800° C. 
     
     
         18 . The method of  claim 1  wherein the reacting of methane and sulfur is conducted at a reactor temperature of from about 600° C. to about 700° C. 
     
     
         19 . The method of  claim 1  wherein the reacting of the produced hydrogen disulfide with methane is conducted at a reactor pressure of from about 0.6 barg to about 4.0 barg. 
     
     
         20 . The method of  claim 1  wherein the reacting of the produced hydrogen disulfide with methane is conducted at a reactor pressure of from about 1.2 barg to about 2.8 barg. 
     
     
         21 . The method of  claim 1  wherein the reacting of the produced hydrogen disulfide with methane is conducted at a reactor temperature of from about 700° C. to about 1100° C. 
     
     
         22 . The method of  claim 1  wherein the reacting of the produced hydrogen disulfide with methane is conducted at a reactor temperature of from about 800° C. to about 1000° C. 
     
     
         23 . The method of  claim 1  which further comprises separating carbon disulfide and hydrogen in the mixture at a temperature of from about −50° C. to about −10° C. and a pressure of from about 0.9 barg to about 1.9 barg. 
     
     
         24 . A system comprising:
 a first reactor configured to react methane and sulfur under conditions sufficient to produce carbon disulfide, hydrogen disulfide, and heat in an exothermic reaction; and   a second reactor operatively coupled to the first reactor, wherein the second reactor is configured to react at least a portion of the produced hydrogen disulfide from the first reactor with methane under conditions sufficient to produce a mixture comprising carbon disulfide and hydrogen in an endothermic reaction;   wherein the first reactor and second reactor are heat integrated such that at least a portion of the heat generated in the exothermic reaction between methane and sulfur in the first reactor is employed to propagate the endothermic reaction between the produced hydrogen disulfide and methane in the second reactor.